Display devices are subject to various tests before release to detect the performance of the display apparatuses. Electro-static discharge (ESD) test is used to detect the anti electro-static performance of display apparatuses. When performing the ESD test, an ESD device discharges toward a hole (such as an earphone interface, or a USB interface) on the display apparatus in a contact or contactless manner. The electrostatic electricity will transfer to the inside of the display apparatus. If the electro-static current is large, the driving circuit inside the display apparatus will become abnormal. For example, the operation voltage of the boost circuit inside the driving circuit is pulled down to a relatively low level, such that the driving circuit cannot drive the display panel.
According to the ESD standard, the products being detected can be classified into 4 levels of A, B, C and D. For level A, all functions of the product are normal and not disturbed during and after the ESD test. For level B, the product performance is temporarily and trivially influenced during and after the ESD test, but it can recover itself after a period of time. For level C, the product performance is influenced during and after the ESD test, and the product can only recover to normal after restarting the system of the product. For level D, the product completely fails during and after the ESD test and cannot recover.
For strict manufacturers, level C is not acceptable. Therefore, it is necessary to improve the capability of anti electro-static electricity of existing display apparatuses. It is preferred that the driving circuit can self-detect its own electro-static electricity, and when the electro-static current exceeds the biggest current that the driving circuit can withstand, the driving circuit can recover itself.